1. Field of the Invention
The present invention relates to automatic swimming pool cleaning apparatus and more particularly to improvements in such cleaners utilizing flexible conduit sweeping arms to agitate silt and particulate debris which accumulates in pools. The flexible conduits of the instant invention exhibit a high degree of motional and scrubbing efficacy due to their compound water discharge means, thereby greatly enhancing their silt agitating ability so as to maintain the silt in suspension and facilitating its removal by well known pump-driven recirculating filtering systems.
2. Description of the Prior Art
In recent years, a considerable amount of effort has been directed towards providing swimming pool cleaning devices of various types. The effort continues even now, to meet the new requirements evolving as this popular recreational form receives wider use due to the emergence of inexpensive pools, and progressively simpler types of pool installations. These new requirements arise from a need for lower cost cleaning devices of substantially portable configurations which may be easily installed and removed without complex or critical adjustments, or special tools.
The earlier prior art discloses a number of hand-manipulated vacuuming devices and methods, used periodically for cleaning the pool water. More recently, a number of automated devices have been disclosed showing a change towards the inclusion of random sinuous motion silt agitation means in conjunction with the well known water recirculating pumping and filtering systems. Pool cleaning systems which employ a combination of random sinuous motion, silt agitation means with conventional pump-driven recirculating/filtering systems, while representing a practical solution to the problem, also have disadvantages which have slowed their widespread acceptance. Typical prior art devices of this type include complex float-supported valve switching mechanisms for reversing the flow of pressurized water, thereby both propelling and guiding their pendently suspended flexible conduit, silt agitating means over the expanse of the pool. Examples of such embodiments may be found in U.S. Pats. to Ortega, Nos. 3,295,540; and to Winston et al, 3,170,180. Other prior art systems of the combination type teach the use of rigid structural members (including mechanically oscillated members) to suspend the flexible conduit into the pool. Exemplary prior art of these latter types are found in the Blumenfeld U.S. Pat. No. 2,191,207 and the Pansini U.S. Pat. No. 3,032,044. All of these prior art devices, including a much simpler embodiment disclosed in the Varian U.S. Pat. No. 3,074,078, have the severe disadvantage of causing excessive frictional wear of the flexible conduit as it traverses throughout the pool. Additionally, they either include complex mechanisms to preclude their becoming stalled, or simply ignore the stalling problem -- in either case causing the devices to perform far less than optimally.
Other disadvantages of the devices disclosed in the related prior art arise from the manner in which the pressurized water is discharged. Flexible conduit arms having only a single discharge nozzle at their outer extremity for propulsion agitate silt mostly by the abrading, wiping action of the arms, and only incidentally by the expulsion of pressurized water from the discharge nozzle. Silt agitation by the nozzle is therefore restricted to the region immediately adjacent to the outlet.